I don't think you will have to many problems with noise up there. We have been up there with many loud boats and never had a problem. As long as you are not out there reving the boat or doing anything crazy, they (rangers) will leave you alone.
As far as hotels go the closest place I know of is Merced, Modesto, Jamestown. someone that lives up that way may know better. You might even want to look at renting a Motorhome.
The lake gets crowded but it is still enjoyable on a holiday weekend. You don't have to deal with long launch lines or anything to that nature. The worst part is parking in my opinion if you are not camping there.